Though it was kind of implied during the iPad 2 event yesterday when we learned that the GSM (that is, non-Verizon) version of the iPhone 4 would be getting iOS 4.3 with mobile hotspot capability on March 11th, we've doubly confirmed with AT&T today that the carrier will be offering the feature right out of the gate -- a departure from the tethering delay of days gone by. Naturally, you'll need the tethering feature added to your account, a $20 surcharge over the standard 2G
